An optical fiber is commonly used in telecommunications for communicating data signals over both short and long distances. With respect to other communication mediums, such as a metal wire, an optical fiber is advantageous in that signals travel along it with less loss, and it is also less susceptible to electromagnetic interference. An optical fiber may also have a relatively high bandwidth. An optical fiber may also be used in other applications, such as a sensor and a laser, for example.
A fiber-optic matrix switch may be used for a variety of network switching applications, and more particularly, for switching applications using optical fibers. Such switches are typically assembled from a fundamental building block, such as a 1×N switch, for example, that can direct an input to any one of N outputs.
Generally, for an optical matrix switch in a particular application, loss, crosstalk, reflection, and switching speed may be considered. Power consumption may also be considered. Cost and duty cycle are other factors that may be considered when selecting an optical matrix switch.
Generally, a relatively large matrix switch (M×N) uses either beam steering or reflection optics based upon microelectromechanical system (MEMS) mirrors in a two dimensional (2D) or a three-dimensional (3D) configuration. A relatively large matrix switch typically requires a 3D geometry. Additionally, a relatively large matrix switch uses free-space propagation of light and a form of collimation optics and generally has losses from recapturing the light into a fiber waveguide. However, this type of matrix switch may be advantageous in that the light may be directed from any input port to any output port without passing through any intervening switching elements, and therefore may be inherently non-blocking. However, the matrix switch generally requires continuous power to operate.
U.S. Pat. No. 6,873,754 to Hatta et al., for example, discloses an optical switch. The optical switch includes a polymer sheet having an optical waveguide extending linearly therein, and keep plates holding the polymer sheet therebetween. The polymer sheet has a notch to traverse the optical waveguides, and the keep plates each have an opening at a position corresponding to the notch.
U.S. Pat. No. 6,005,993 to MacDonald discloses an optical matrix switch. The optical matrix switch includes glass blocks that are moved relative to another glass block to route light. The glass blocks contact each other via an elastomer index matching element.